依替二膦酸锶对大鼠腰椎及股骨生物力学的性质的影响

The effect of strontium etidronate on the biomechanics of rat lumbar vertebrae and femurs

目的观察新合成的抗骨质疏松化合物依替二膦酸锶对骨组织生物力学的影响。方法以去势SD大鼠为基础,对依替二膦酸锶、依替二膦酸二钠和二氯化锶以及不同剂量依替二膦酸锶对大鼠股骨及腰椎生物力学性质的影响进行动态观察和比较。结果依替二膦酸二钠治疗12 w后其股骨的最大负荷升高9.5%(P=0.028),并且其差异表现出统计学意义;依替二膦酸锶治疗组8 w、12 w后,其股骨的最大负荷分别升高21.9%和22.3%(P=0.020,P=0.047),且均表现出统计学差异。3种不同药物治疗下,股骨于最大负荷下的变形没有明显变化。所有治疗组大鼠椎体的最大负荷均高于去势对照组。依替二膦酸锶治疗12 w后,其椎体的最大负荷明显升高(P=0.016),并表现出统计学差异。观察到100 mg/(kg·d)和150 mg/(kg·d)治疗组干预8 w后,其股骨最大负荷升高(P=0.035,P=0.042),并表现出统计学意义;椎体最大负荷于也明显升高(P=0.018),并表现出统计学意义。大鼠股骨他椎体于最大负荷时的椎体变形并未表现出统计学意义。实验发现依替二膦酸锶与依替二膦酸二钠相比,对去势大鼠腰椎和股骨生物力学性质的影响更为明显。其干预后去势大鼠骨组织生物力学性质的出现更早,且其升高的幅度也较高。50 mg/(kg·d)、100 mg/(kg·d)和150 mg/(kg·d)3种不同剂量的依替二膦酸锶均能有效地改善去势大鼠椎体和股骨的生物力学性质,且其改善生物力学性质的能力无明显差异。结论新化合物中的骨吸收抑制物依替二膦酸和骨形成促进物锶进入大鼠体内后,两者的生物学效应可能存在互补性。

Objective To investigate the effect of the new compound strontium etidronate on bone biomechanics.Methods Using ovariectomized SD rats, the effect of didodium etidronate, strontium chloride, and different doses strontium etidronate on the femoral and vertebral bone biomechanical property was dynamically observed and compared.Results The rat femoral Max load improved by 9.5%after 12-week intervention of didodium etidronate （P=0.028）, and the result was statistical different.The rat femoral Max load improved by 21.9% and 22.3%, respectively, after 8-and 12-week intervention of strontium etidronate （ P=0.020, P=0.047）, and the results were statistical different.The femoral deformation under the Max load showed no different change when intervened with the above three substances.The Max load of the vertebrae in all treatment groups was higher than that in OVX group.The Max load of the vertebrae improved significantly after 12-week treatment of strontium etidronate （P=0.016）. Both the femoral Max load and the lumbar Max load improved in 100 mg/kg？d （P=0.035, P=0.042） and 150 mg/kg？d （P=0.018） strontium etidronate treatment groups in 8 weeks.No statistical difference of femoral and lumbar deformation was shown under the Max load.The lumbar and femoral biomechanics improved more in strontium etidronate group than in didodium etidronate group.and the biomechanical improvement appeared earlier and more.Strontium etidronate of different doses （50 mg/kg？d, 100 mg/kg？d, and 150 mg/kg？d） improved the lumbar and femoral biomechanics of ovariectomized rats effectively.The efficacy among the three different doses showed no obvious difference.Conclusion The new compounds, etidronate for inhibition of bone resorption and strontium for stimulation of bone formation, show complement biological effect in vivo.